With the constant development of computer technology, there has been an increased demand for change on requirements on file systems. Usually a file system manages file storage by maintaining a logical storage block, the logical storage block corresponding to a physical storage block that is used for actual file storage. In practice, variable file block size is of considered as an important factor in designing and implementing a file system. Specifically, variable file block size can decrease the occupation of metadata, improve the I/O performance and reduce fragments.
However, though most modern file systems can support different block size, in general only one block size will be used while creating the file system and the block size typically cannot be changed during the lifecycle of the file system. Therefore, in the prior art there lacks a flexible and efficient management style of file systems, and it becomes difficult to take full advantage of the flexibility of file systems.